Is it selfish?

We have one daughter and I’m expecting again...we don’t know the sex yet. My husband says if it’s a girl he wants to try again for a boy. Honestly, I don’t want three kids. I’ve told him that. I get hardly any help with the one we have now since my husband works all the time. I do all the housework, work 3x a week, take care of our child (feeding, changing, bathing, bedtime, doing her laundry, picking up after her, literally everything), take care of our dogs....I am nervous about adding one more kid, let alone possibly two. Is it selfish of me to want to be done after this baby?